Rationally engineered chiral phase-transfer catalysts in the alkylation of substituted 2-alkyl -1-indanones

ORGN 765

Thomas Anthony Ramirez, t103180@aol.com1, Tomas Vasques1, Robert Erik Plata1, Jiejun Wu, jwu7@prdus.jnj.com2, and Apurba Bhattacharya1. (1) Department of Chemistry, Texas A&M University-Kingsville, 920 West Santa Gertrudis, MSC 161, Kingsville, TX 78363, (2) J&J Pharmaceutical Research & Development, LLC, 3210 Merryfield Row, San Diego, CA 92121
Enantioselective alkylations of differentially functionalized 2-alkyl-1-indanones catalyzed by chiral phase-transfer catalysts derived from cinchona alkaloids are under investigation. The results of these experiments, along with kinetic studies, shed further light on the enzyme/substrate-like electronic complimentarity and the factors responsible for improved enantioselectivity. 2-alkyl-1-indanones were chirally alkylated with 1,3-dichloro-2-butene. Structure of the substrate as well as electronic factors influence the enantiomeric excess. The presence of electron-donating groups in the indanone nucleus cause a low enantiomeric excess whereas electron-poor groups cause a high enantiomeric excess. The interaction between the catalyst and the substrate can be electronically tuned to make efficient chiral catalysts that will result in high enantiomeric excesses. Utilization of this technology to make functionalized chiral indanones is in progress.